If all of this just needs to be posted in your thank-you pages, and you're using your standard E-junkie-generated thank-you pages (rather than redirecting to a thank-you page URL on your site), you could insert most of the required order details by using our template tags documented here:
http://www.e-junkie.com/ej/help.custom.thankyou-page.htm
The section for general order and merchant information would go in your Common Thank-you Page HTML field (Seller Admin > Account Preferences), and the section for item specific information would go in each product's Message (HTML) field. You would place the template tag where its information should be inserted, like so:
<span id="gts-o-id">[%txn_id%]</span>
When we generate the page to display to the buyer, that [%txn_id%] tag would be replaced with their order's actual Transaction ID before we send the page to their browser. You may need to use javascript to massage the data or provide data our system doesn't handle.
E.g., our 'txn_id' for Google Wallet/Checkout adds a prefix "gc-" to the standard Google checkout Order Number, so if they require the original Order Number in the line:
<span id="gts-o-id">MERCHANT_ORDER_ID</span>
...you'd need to put the [%txn_id%] inside some custom javascript that could remove the "gc-" prefix and insert the remaining ID in that span.
Since our system doesn't track ship dates, you could use custom javascript to calculate a date 5 (or however many) days past the current date and insert the resulting date in:
<span id="gts-o-est-ship-date">ORDER_EST_SHIP_DATE</span>
All that said, what happens if the buyer never clicks past the end of checkout to view their thank-you page at all? PayPal and Google Wallet/Checkout do not auto-redirect the buyer to any thank-you page after checkout, so if the buyer has no reason to do so (such as claiming a download), they might never trigger any tracking code placed in that page.
All that said, it seems like the requirements you posted above might be intended for use with a "licensed", full-featured ecommerce software package that gets installed on your server, which controls every step of the shopping and checkout experience as a self-contained solution operating entirely on your own server. E-junkie is a "hosted" service where we manage the shopping cart software for you on our own servers, and we hand-off checkouts entirely to a third-party payment processor such as PayPal or Google Wallet/Checkout, so we don't provide the degree of complete control that this Trusted Stores implementation might require.